The present invention relates generally to heat exchange catheters.
The present assignee has provided heat exchange catheters for controlling a patient""s temperature at normothermia to alleviate fever, which is standard of care for neuronally injured patients, and for establishing mild to moderate hypothermia in patients presenting symptoms of stroke, cardiac arrest, myocardial infarction, high intercranial pressure, brain trauma, and other neuronal injury-related diseases. The catheters can be used for controlled rewarming of the patients. Examples of such catheters are disclosed in U.S. Pat. Nos. 6,149,670 and 6,126,684, incorporated herein by reference.
The present invention is directed to a heat exchange catheter with a relatively high heat transfer rate.
A heat exchange catheter includes a catheter body and a working fluid supply lumen in the body. A helical heat exchange tube communicates with the supply lumen and extends along the outside surface of the body for exchanging heat with a body fluid when the body is disposed in a patient.
In a preferred embodiment, the heat exchange tube establishes plural coils that are bonded to the body at respective bond points. The coils otherwise are distanced from the body when fluid is circulated through the heat exchange tube. In one preferred implementation, coolant flows distally through the supply lumen and generally proximally through the heat exchange tube.
As set forth further below, the preferred supply lumen is established by a supply tube, and the supply tube preferably is made integrally with the heat exchange tube. Also, at least two working lumens can extend through the catheter body and terminate at respective infusion ports that are longitudinally spaced from each other along the catheter body.
A proximal hub can be engaged with the body and can establish a suture anchor. One or more central venous components preferably communicate with the hub. Additionally, a heater/chiller communicates with the supply lumen and heat exchange tube via the hub to heat or cool the working fluid.
In another aspect, a catheter includes a body supplying working fluid from a proximal heater/chiller toward a distal location on the body. A helical tube surrounds part of the body and communicates with the working fluid such that blood can flow between the tube and body to exchange heat with the working fluid.
In still another aspect, a system for exchanging heat with a patient includes a heater/chiller supplying a working fluid, and a helical heat exchanger disposable in the patient and communicating with the heater/chiller. As contemplated herein, the heat exchanger establishes plural coils and an axis, with the coils being configured to allow blood flow between the coils and the axis and between the coils and a vessel wall.
The details of the present invention, both as to its structure and operation, can best be understood in reference to the accompanying drawings, in which like reference numerals refer to like parts, and in which: